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In order to explore the microstructure and micromechanical properties of Cu - rich Ni - Cu - P coating synthesized through electroless plating, such coating was synthesized on the 45 steel substrate by electroless plating. The SEM, XRD, EDS, microhardness tester and nanoindenter were used to test the microstructure and micromechanical properties of the coating without heat treatment and after heat treatment. Results showed that a uniform Cu - rich Ni - Cu - P coating was obtained, which showed good adhesion with the 45 steel substrate. With the prolongation of plating time, the content of Cu in the coating decreased while the content of Ni and P increased. The coating without heat treatment was mainly composed of Cu - and Ni - based solid solutions. After a heat treatment at 200 ℃ or 300 ℃ for 2 h, the phase composition of the coating showed no obvious change. However, after a heat treatment at 400 ℃, NiP2 and Cu3P were precipitated from the coating. In the early stage of plating (10 min), the hardness of coating increased obviously with the prolonging of the plating time, but after that a sluggish increase appeared. In all, a heat treatment, especially at 400 ℃ for 2 h, could promote the precipitation of phosphide and thus increase the hardness of coating.

Objective: The drug-loaded PEGylated nanomaterials have shown effective cell-killing in vitro, but to the best of authors' knowledge there have been no reports of successful drug delivery in vitro and in vivo using polyethyleneglycol-2000-distearoyl phosphatidyl ethanolamine (PEG2000-DSPE) nanomaterials loaded with unmodified drug molecules, such as quercetin (QUE). In this study, it remained an open question as to whether such formulations could prove effective in vitro and in vivo, and to study the distribution and clearance of PEG-DPSE-ylated lipid-based quercetin nanoliposomes (PEG2000-DPSE-QUE-NLs) as delivery vehicles for the anticancer drug in vitro and in vivo., Research Design and Methods: PEG-DPSE layers were attached to QUE-NLs, dispersed in aqueous media and characterized using TEM and HPLC/UV spectroscopy. Tumor cell killing efficacy was assessed in vitro using MTT and trypan blue exclusion assays, and the distribution and clearance pathways, as well as repeated administration in rats, were studied by HPLC spectroscopy., Results: PEG2000-DPSE-QUE-NLs were efficiently dispersed in aqueous media compared with controls, and PEGylated (PEG2000-DPSE) NLs were found to be effective drug delivery vehicles when simply loaded with QUE. The plasma QUE concentration decreased significantly (p < 0.05) after repeated administration of PEG2000-DSPE liposomal QUE. There was a slight ABC phenomenon with the PEG2000-DSPE-modified QUE liposomes., Conclusion: The QUE/PEG2000-DPSE formulation was more effective than QUE in vitro on inhibiting the growth of glioma cancer cells. This work demonstrates that nanomaterials (PEG2000-DPSE) are effective drug delivery vehicles in vivo as tumor-targeted drug carriers.